Imaging Acute and Chronic Cardiac Complications of COVID-19 and after COVID-19 Vaccination.

COVID-19 is associated with acute and longer-term cardiovascular manifestations including myocardial injury, myopericarditis, stress-induced cardiomyopathy, myocardial infarction, and thromboembolic disease. Although the morbidity and mortality related to acute COVID-19 have decreased substantially, there is growing concern about the longer-term cardiovascular effects of the disease and postacute sequelae. Myocarditis has also been reported after messenger ribonucleic acid (mRNA)-based COVID-19 vaccination, with the highest risk among adolescent boys and young adult men. Noninvasive imaging including cardiac MRI has a key role in identifying the presence of cardiovascular disease, evaluating for potential mechanisms of injury, stratifying risk of future adverse cardiovascular events, and potentially guiding treatment in patients with suspected cardiovascular injury after COVID-19 and vaccination. Patterns of injury identified at cardiac MRI after COVID-19 include myocarditis and pericarditis, myocardial ischemia, and infarction. Myocardial edema and late gadolinium enhancement have been described months after the initial infection in a minority of patients with persistent cardiac symptoms after COVID-19. In patients with myocarditis after receiving a COVID-19 vaccination, the most common pattern of late gadolinium enhancement is subepicardial at the basal inferolateral wall, and patients tend to have milder imaging abnormalities compared with those from other causes of myocarditis. This article describes the role of multimodality cardiac imaging and imaging findings in patients with acute and longer-term cardiovascular manifestations of COVID-19 and in patients with myocarditis after receiving an mRNA-based COVID-19 vaccination. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

Prognostic Value of Different Thresholds for Myocardial Scar Quantification on Cardiac MRI Late Gadolinium Enhancement Images in Patients Receiving Implantable Cardioverter Defibrillators.

Purpose: To compare the predictive value of different myocardial scar quantification thresholds using cardiac MRI for appropriate implantable cardioverter defibrillator (ICD) shock and mortality. Materials and Methods: In this retrospective, two-center observational cohort study, patients with ischemic or nonischemic cardiomyopathy underwent cardiac MRI prior to ICD implantation. Late gadolinium enhancement (LGE) was first determined visually and then quantified by blinded cardiac MRI readers using different SDs above the mean signal of normal myocardium, full-width half-maximum, and manual thresholding. The intermediate signal "gray zone" was calculated as the differences between different SDs. Results: Among 374 consecutive eligible patients (mean age, 61 years ± 13 [SD]; mean left ventricular ejection fraction, 32% ± 14; secondary prevention, 62.7%), those with LGE had a higher rate of appropriate ICD shock or death than those without (37.5% vs 26.6%, log-rank P = .04) over a median follow-up of 61 months. In multivariable analysis, none of the thresholds for quantifying scar was a significant predictor of mortality or appropriate ICD shock, while the extent of gray zone was an independent predictor (adjusted hazard ratio per 1 g = 1.025; 95% CI: 1.008, 1.043; P = .005) regardless of the presence or absence of ischemic heart disease (P interaction = .57). Model discrimination was highest for the model incorporating the gray zone (between 2 SD and 4 SD). Conclusion: Presence of LGE was associated with a higher rate of appropriate ICD shock or death. Although none of the scar quantification techniques predicted outcomes, the gray zone both in infarct and nonischemic scar was an independent predictor and may refine risk stratification.Keywords: MRI, Scar Quantification, Implantable Cardioverter Defibrillator, Sudden Cardiac Death Supplemental material is available for this article. © RSNA, 2023.

A Combined Echocardiography Approach for the Diagnosis of Cancer Therapy-Related Cardiac Dysfunction in Women With Early-Stage Breast Cancer.

IMPORTANCE: Diagnosis of cancer therapy-related cardiac dysfunction (CTRCD) remains a challenge. Cardiovascular magnetic resonance (CMR) provides accurate measurement of left ventricular ejection fraction (LVEF), but access to repeated scans is limited. OBJECTIVE: To develop a diagnostic model for CTRCD using echocardiographic LVEF and strain and biomarkers, with CMR as the reference standard. DESIGN, SETTING, AND PARTICIPANTS: In this prospective cohort study, patients were recruited from University of Toronto-affiliated hospitals from November 2013 to January 2019 with all cardiac imaging performed at a single tertiary care center. Women with human epidermal growth factor receptor 2 (HER2)-positive early-stage breast cancer were included. The main exclusion criterion was contraindication to CMR. A total of 160 patients were recruited, 136 of whom completed the study. EXPOSURES: Sequential therapy with anthracyclines and trastuzumab. MAIN OUTCOMES AND MEASURES: Patients underwent echocardiography, high-sensitivity troponin I (hsTnI), B-type natriuretic peptide (BNP), and CMR studies preanthracycline and postanthracycline every 3 months during and after trastuzumab therapy. Echocardiographic measures included 2-dimensional (2-D) LVEF, 3-D LVEF, peak systolic global longitudinal strain (GLS), and global circumferential strain (GCS). LVEF CTRCD was defined using the Cardiac Review and Evaluation Committee Criteria, GLS or GCS CTRCD as a greater than 15% relative change, and abnormal hsTnI and BNP as greater than 26 pg/mL and ≥ 35 pg/mL, respectively, at any follow-up point. Combinations of echocardiographic measures and biomarkers were examined to diagnose CMR CTRCD using conditional inference tree models. RESULTS: Among 136 women (mean [SD] age, 51.1 [9.2] years), CMR-identified CTRCD occurred in 37 (27%), and among those with analyzable images, in 30 of 131 (23%) by 2-D LVEF, 27 of 124 (22%) by 3-D LVEF, 53 of 126 (42%) by GLS, 61 of 123 (50%) by GCS, 32 of 136 (24%) by BNP, and 14 of 136 (10%) by hsTnI. In isolation, 3-D LVEF had greater sensitivity and specificity than 2-D LVEF for CMR CTRCD while GLS had greater sensitivity than 2-D or 3-D LVEF. Regression tree analysis identified a sequential algorithm using 3-D LVEF, GLS, and GCS for the optimal diagnosis of CTRCD (area under the receiver operating characteristic curve, 89.3%). The probability of CTRCD when results for all 3 tests were negative was 1.0%. When 3-D LVEF was replaced by 2-D LVEF in the model, the algorithm still performed well; however, its primary value was to rule out CTRCD. Biomarkers did not improve the ability to diagnose CTRCD. CONCLUSIONS AND RELEVANCE: Using CMR CTRCD as the reference standard, these data suggest that a sequential approach combining echocardiographic 3-D LVEF with 2-D GLS and 2-D GCS may provide a timely diagnosis of CTRCD during routine CTRCD surveillance with greater accuracy than using these measures individually. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02306538.

Prognostic value of cardiovascular magnetic resonance left ventricular volumetry and geometry in patients receiving an implantable cardioverter defibrillator.

BACKGROUND: Current indications for implantable cardioverter defibrillator (ICD) implantation for sudden cardiac death prevention rely primarily on left ventricular (LV) ejection fraction (LVEF). Currently, two different contouring methods by cardiovascular magnetic resonance (CMR) are used for LVEF calculation. We evaluated the comparative prognostic value of these two methods in the ICD population, and if measures of LV geometry added predictive value. METHODS: In this retrospective, 2-center observational cohort study, patients underwent CMR prior to ICD implantation for primary or secondary prevention from January 2005 to December 2018. Two readers, blinded to all clinical and outcome data assessed CMR studies by: (a) including the LV trabeculae and papillary muscles (TPM) (trabeculated endocardial contours), and (b) excluding LV TPM (rounded endocardial contours) from the total LV mass for calculation of LVEF, LV volumes and mass. LV sphericity and sphere-volume indices were also calculated. The primary outcome was a composite of appropriate ICD shocks or death. RESULTS: Of the 372 consecutive eligible patients, 129 patients (34.7%) had appropriate ICD shock, and 65 (17.5%) died over a median duration follow-up of 61 months (IQR 38-103). LVEF was higher when including TPM versus excluding TPM (36% vs. 31%, p < 0.001). The rate of appropriate ICD shock or all-cause death was higher among patients with lower LVEF both including and excluding TPM (p for trend = 0.019 and 0.004, respectively). In multivariable models adjusting for age, primary prevention, ischemic heart disease and late gadolinium enhancement, both LVEF (HR per 10% including TPM 0.814 [95%CI 0.688-0.962] p = 0.016, vs. HR per 10% excluding TPM 0.780 [95%CI 0.639-0.951] p = 0.014) and LV mass index (HR per 10 g/m2 including TPM 1.099 [95%CI 1.027-1.175] p = 0.006; HR per 10 g/m2 excluding TPM 1.126 [95%CI 1.032-1.228] p = 0.008) had independent prognostic value. Higher LV end-systolic volumes and LV sphericity were significantly associated with increased mortality but showed no added prognostic value. CONCLUSION: Both CMR post-processing methods showed similar prognostic value and can be used for LVEF assessment. LVEF and indexed LV mass are independent predictors for appropriate ICD shocks and all-cause mortality in the ICD population.